I saw a very old posting. Do you still have this amp and are you still listening to it ?
I bought one (without volume control) and am using it with a Creek passive pre amp and Senn 600's. It sounds great to me but then again I listen through regular full sized speakers most of the time so have nothing much to compare it too, headphone rig wise.
I don't want to get rid of it or anything. Just wondered what other listeners thought that's all.